4. A bag contains 4 red and 6 blue marbles. A marble is chosen at random but not
replaced in the bag. A second marble is then chosen at random. Given that the
second marble is blue, what is the probability that the first marble is also blue?
Two fair tetrahedral dice, each with the numbers 1, 2, 3 and 4 marked on the faces, are
thrown together. One die is red and the other is green. The score on each die (the
number on the face which cannot be seen) is noted.
A is the event: the score on the red die is 3
B is the event: the sum of the scores is 6
C is the event: the scores on the two dice are the same
D is the event: the score on the green die is less than the score on the red die
6. What is P(A | B) ?
7. What is P(D | C''')
8. Which statement is true?
(a) A and B are independent events (b) A and C are independent events
(c) A and D are independent events (d) B and C are independent events
replaced in the bag. A second marble is then chosen at random. Given that the
second marble is blue, what is the probability that the first marble is also blue?
Two fair tetrahedral dice, each with the numbers 1, 2, 3 and 4 marked on the faces, are
thrown together. One die is red and the other is green. The score on each die (the
number on the face which cannot be seen) is noted.
A is the event: the score on the red die is 3
B is the event: the sum of the scores is 6
C is the event: the scores on the two dice are the same
D is the event: the score on the green die is less than the score on the red die
6. What is P(A | B) ?
7. What is P(D | C''')
8. Which statement is true?
(a) A and B are independent events (b) A and C are independent events
(c) A and D are independent events (d) B and C are independent events